Zenith ZP-150
| Developer | Zenith Data Systems | 
|---|---|
| Manufacturer | Zenith Data Systems | 
| Type | Laptop | 
| Release date | 1984 | 
| Operating system | System Manager | 
| CPU | Intel 80C88 | 
| Memory | 224 KB | 
| Display | LCD, 80 x 16 characters | 
| Successor | Z-181, Z-183 | 
The ZP-150 was one of the earliest commercially available laptops. It was released in late 1984 by Zenith Data Systems.
Market life
The ZP-150 was offered for US$1,995 when bundled with the US$800 Microsoft Works software, but could be found in the Fall 1985 Heathkit catalog for US$1,195. The price came down to US$999 in the Winter 1986 edition of the same catalog and US$699 in the Fall 1987 edition, as it was being phased out with the release of the Z-181 and Z-183. The main target market was the U.S. government and "the mobile executive", for on-site applications. Its relatively small dimensions and light weight allowed it to be easily carried in a standard briefcase or the included carrying case.
Hardware specifications
- Weight: 7.7 lb (3.5 kg)
 - Dimensions: 13"W × 11.1"D × 1.8"H
 - RAM: 32K, expandable to 416K
 - ROM: 224K, plus 2 sockets for software expansion
 - CPU: Intel 80C88
 - Power: 12VDC or 10 AA alkaline batteries (providing 15 hours run-time w/o modem), plus internal nickel-cadmium battery for retaining memory while off, up to 8 days
 - Ports:
 
- Parallel printer
 - RS-232C
 - Telephone line (300 baud modem)
 - System bus
 - BCR (for a bar code reader)
 - CMT (for data cassette recorder)
 - ACP (for acoustic coupler)
 - Handset (of telephone)
 
- LCD display (80 characters/line with 16 lines), contrast control, volume control, and low-battery indicator
 - 75-key typewriter-style keyboard
 
The stock 32K RAM could hold up to 10 typewritten pages. The main methods of file transfer were via the modem or the RS-232C port and a file transfer program.
Software specifications
The ZP-150 came with a built-in System Manager and calculator program, as well as a special version of Microsoft Works 1.10 stored in ROM. Most programs are very similar to the desktop versions, but with reduced functionality.
- Word word processor
 - Plan electronic spreadsheet, similar to Multiplan (spreadsheet size up to 255 rows x 63 columns)
 - Calendar appointment organizer with alarm
 - File database manager
 - Telcom telecommunications package
 - BASIC program editor and compiler
 
Accessories
- ZP-150-1 power transformer
 - ZP-150-2 32K RAM module
 - ZP-150-4 Parallel to Centronics printer cable
 - CB-5063-27 File transfer software
 
Historical significance
The most significant aspect of the ZP-150's history is that it is not remembered as one of the first portable computers, despite its relatively early appearance in the marketplace and being referred to in advertising as a "laptop". Like the IBM PC and Apple II computers, the ZP-150 was quickly copied. The most well-known clone is the Tandy 600, which was very similar in packaging, software, and hardware except for the addition of a floppy drive and the lacking of BASIC. This was not the first laptop that Tandy manufactured, but was one in the TRS-80 line.
See also
References
- ZP-150 User's guide, (1985) Zenith Data Systems Corporation, St. Joseph, MI and Heath Company, Benton Arbor, MI
 - Heathkit catalogs, Fall 1985 (No. 870R) pp90-91, Winter 1986 (No. 201) p89, Fall 1987 (No, 207) p84
 - OLD-COMPUTERS.com Museum Archived 2006-11-23 at the Wayback Machine TRS-80 Model 600
 - 8bit-Micro.com - TRS-80 Laptops
 
External links
- IEEE Annals of the History of Computing
 - Tandy 600 and Zenith ZP150 photographic comparison of the internal hardware of the Tandy 600 and the Zenith ZP-150
 - Zenith Data Systems company timeline Archived 2006-12-18 at the Wayback Machine
 - "Zenith ZP-150, 360 degree model", Russian Vintage Laptop Museum (museum), 6 April 2017